Material exchange frequently occurs in gullies,and thus the relationship between a gullynetwork structure and sediment transport potential has attracted considerable interest.However,previous researches ignored the di...Material exchange frequently occurs in gullies,and thus the relationship between a gullynetwork structure and sediment transport potential has attracted considerable interest.However,previous researches ignored the difficulty of material transport from sources to sinks,and did not quantify the connectivity of a network structure.In this study,we used a graph model structure to model gully networks of six typical sample areas in the Loess Plateau of China and quantified gully network connectivity using four indexes:average node strength,accessibility from sources to sinks,potential flow,and network structural connectivity index.Results show that:(1)Reflected by different quantitative indexes,the trends of gully network connectivity in different regions are similar.From north to south,the connectivity of a sample area first increases and then decreases.(2)The more mature gullies have stronger network connectivity.Small resistance is conducive to material transport in the gullies.(3)The node connectivity index of the gully network shows a significant aggregation distribution in space,and node connectivity on the main channel is often stronger than that on the branch trench.These results not only deepen the understanding of the process and mechanism of loess gully geomorphic development and evolution but also provide a reference for geomorphic studies.展开更多
Urban green innovation(UGI)is essential to environmental protection,ecological conservation,and high quality economic growth.Using green patents,our study assessed the level of UGI of 287 Chinese cities at and above t...Urban green innovation(UGI)is essential to environmental protection,ecological conservation,and high quality economic growth.Using green patents,our study assessed the level of UGI of 287 Chinese cities at and above the prefecture level.Then,using the Dagum Gini coefficient,kernel density estimation(KDE),and con‐vergence models,we examined regional differences,distribution dynamics,and convergence of UGI across China.The study’s findings are as follows:(1)Overall,regional differences in UGI tended to narrow,and the main contributor to these differences was the difference between economic zones.(2)KDE showed that the level of UGI was rising,which was polarized within each economic zone.(3)The national UGI in economic zones other than the Northeast and Middle Yellow River Economic Zones featured significantσconvergence,while each economic zone showed absolute and conditionalβconvergence.展开更多
To achieve the goals of carbon peaking and carbon neutrality and maintain high-quality economic growth,China is currently striving to improve the quality of development of its power sector.In this regard,revealing the...To achieve the goals of carbon peaking and carbon neutrality and maintain high-quality economic growth,China is currently striving to improve the quality of development of its power sector.In this regard,revealing the regional differences and evolutionary trends in the development quality of China’power sector has a high value to inspire the next improvement direction toward how to integrate regional power recourses to an overall optimization level.Motived by this purpose,this paper uses the entropy method to evaluate the com‐prehensive and subsystem indices of the development quality of the power industry,and reveals their re‐gional differences and evolutionary trends with the help of the Dagum Gini coefficient and Kernel density es‐timation methods.The findings show that:There are obvious regional differences in the development quality of China’s power industry,and the differences are steadily declining in all regions except the West.Regional differences are mainly derived from inter-regional differences,with the largest inter-regional differences in the East-Northeast region.Intra-regional differences show a distribution pattern of East>West>North‐east>Center.展开更多
As an essential infrastructure,the rural power grid is vital in promoting agricultural and rural carbon sequestration and improving rural energy electrification.It is necessary to carry out in-depth research on its co...As an essential infrastructure,the rural power grid is vital in promoting agricultural and rural carbon sequestration and improving rural energy electrification.It is necessary to carry out in-depth research on its comprehensive efficiency.Based on the requirements of“double carbon”and rural revitalization strategy for the rural Power Grid,this paper focuses on the modernization and low-carbon transformation of the rural Power Grid.It constructs an input-output index system for the investment efficiency of the rural Power Grid in China under the new situation.It uses the primary data of the rural Power Grid of 30 prefecture-level cities in China from 2019 to 2021 to evaluate the investment efficiency of the rural Power Grid in China through a three-stage DEA model.The empirical results show that:considering the regional differences,the comprehensive efficiency of the rural Power Grid in backward areas is significantly improved;that is,the three-stage DEA method can more objectively evaluate the comprehensive efficiency of the rural Power Grid.In the context of the continued promotion of the rural revitalization strategy,to improve the comprehensive efficiency of the rural Power Grid,it is necessary to improve the technical level of the rural Power Grid further and appropriately expand the scale of investment in the rural Power Grid.展开更多
Purpose: Obtaining high peak bone mass (PBM) and maintaining bone mass is important for the prevention of osteoporosis. This study aimed to examine the regional differences in bone mineral density and factors associat...Purpose: Obtaining high peak bone mass (PBM) and maintaining bone mass is important for the prevention of osteoporosis. This study aimed to examine the regional differences in bone mineral density and factors associated with its acquisition from exercise. Design: The study population included 75 women of 18 - 22 years of age in East Japan and 104 women of 18 - 27 years of age in West Japan. The speed of sound (SOS) of the calcaneus was measured, and the young adult mean (%YAM) was calculated from the SOS. The subjects’ medical history, family history of osteoporosis, and exercise habits were examined using a self-administered questionnaire. Results: There were a significantly greater number of subjects with low %YAM in West Japan. The exercise history and exercise time were significantly higher in West Japan, and the exercise intensity score tended to be higher in East Japan during junior high and high school. A multiple regression analysis by region revealed that the following factors had a significant positive association with the SOS: exercise intensity at elementary school and outdoor sports at junior high school in East Japan;and exercise time at elementary school, muscle mass, and outdoor sports at junior high school in West Japan. On the other hand, exercise time in junior high school in West Japan showed a negative association with the SOS. Conclusions: Regional differences in bone mineral density existed, suggesting a trend toward lower bone mineral density in West Japan. Exercise history and time tended to be higher in West Japan, and exercise intensity scores tended to be higher in East Japan, suggesting that exercise intensity may be more important than exercise time for obtaining bone mineral density.展开更多
Global warming triggers shrinking and thinning of glaciers worldwide,with potentially severe implications for human society.However,regional differences in glacier retreat and its relationship with climatic characteri...Global warming triggers shrinking and thinning of glaciers worldwide,with potentially severe implications for human society.However,regional differences in glacier retreat and its relationship with climatic characteristics have not been conclusively demonstrated.In this study,regional changes in global glaciers based on two primary features,area change and mass balance,were investigated on the basis of data collected from published research on glacier changes.Results show that during the period 1980—2015,the rate of global glacier area shrinkage was 0.18%per year and that of global glacier mass loss was 0.25 m w.e.per year.Retreat of glaciers located at low and middle latitudes was characterized by severe area shrinkage and mass loss.Correspondingly,in the Arctic,deglaciation was characterized by ice thinning due to a low area reduction but relatively high mass loss rate.However,glaciers in high southern latitudes were in a relatively stable status.High Mountain Asia exhibited the lowest rate of area shrinkage and mass loss among glaciers located at low and middle latitudes,and a slower rate of mass loss compared with the global average.Glaciers in the Tropical Andes exhibited the fastest rate of glacier area shrinkage(—1.6%per year),whereas Antarctic and Subantarctic glaciers showed the lowest rate(—0.11%per year).For mass balance,the most negative occurred at Southern Andes(—0.81 m w.e.per year),followed by Alaska(-0.74 m w.e.per year).Only the Antarctic and Subantarctic experienced small mass gain(0.04 m w.e.per year).High levels of correlation are found between the rates of glacier retreat and annual average temperature and annual total precipitation instead of their trends.The variability of the surface climate conditions in the glacier environment plays a key role in driving these regional differences in global glacier retreat.展开更多
Based on data over 31 provinces and cities in China from2006 to 2013,this thesis first divides those 31 provinces and cities into four economic regions including northeastern region,central region,eastern region and w...Based on data over 31 provinces and cities in China from2006 to 2013,this thesis first divides those 31 provinces and cities into four economic regions including northeastern region,central region,eastern region and western region.Based on data over 31 provinces and cities in China from 2006 to 2013,those 31 provinces and cities were devided into four economic regions in this thesis,including northeastern region,central region,eastern region and western region.Then,it takes international tourism foreign exchange earnings as the dependent variable,the four economic regions as the factor to measure the difference of international tourism foreign exchange earnings in different regions,and finds out the main reasons of it.Through the one-way variance analysis on international tourism foreign exchange earnings,we can know that international tourism foreign exchange earnings have differences in different regions apparently.Besides,significant differences can be found between northeastern and central regions as well as eastern and western regions,while it is not the same case between the central and western regions.展开更多
The improvement of the technical efficiency of energy use has been widely seen as an important way to alleviate energy scarcity.However,the energy rebound effect demonstrates the vulnerability and unsustainability of ...The improvement of the technical efficiency of energy use has been widely seen as an important way to alleviate energy scarcity.However,the energy rebound effect demonstrates the vulnerability and unsustainability of alleviating energy scarcity relying on technology.Under the background of the consistent development of energy factor market,it is of great importance to explore the paths and differences of energy source allocation constrained by technology and cost to promote the sustainable use of energy.This study analyzed the regional differences and threshold characteristics in the impact of the technical and cost efficiency of energy use on energy scarcity using the instrumental variable-two-stage least square method,based on the panel data of Chinese provinces from 2003 to 2017.The results showed that:①Technology and price were the critical forces of the technical and cost efficiency of energy use.They changed the degree of use of surplus production factors by affecting the complementary and replacement demand relationship between energy and non-energy factors.Meanwhile,the impact of energy use efficiency on energy scarcity showed regional and time features due to the different technology capabilities and different levels of market development in different regions and different time.②The alleviation of energy scarcity at the national level relied on the improvement of energy cost efficiency.At the regional level,the alleviation of energy scarcity in central China came from the improvement of the technical efficiency of energy use.However,the alleviation of energy scarcity in the eastern and western regions was due to the improvement of energy cost efficiency.③Constrained by the economic development,openness,science and technology input and the industrial development structure,the impact of the technical and cost efficiency of energy use on energy scarcity demonstrated a nonlinear feature.And structural mutation occurred after passing a specific‘inflection point’,which showed a significant threshold feature.Therefore,energy price should play an important role in energy use and it is necessary to pay attention to the regional differences and time characteristics of energy economic development to promote the sustainable development of energy resources.展开更多
City size distribution is of interest because of a number of key stylized facts, including notably Zipf's law for cities and the importance of urban primacy. But a new and more efficient method Gini index can be u...City size distribution is of interest because of a number of key stylized facts, including notably Zipf's law for cities and the importance of urban primacy. But a new and more efficient method Gini index can be used for calculating regional city size distribution. This paper begins by developing a calculation method for the Gini index, dividing the whole country into 26 areas and then calculating each area's Gini index value. Based on these calculation results, this paper gives a preliminary study on regional differences of its city size distribution and the dynamics.展开更多
Electricity productivity is regarded as a major assessment indicator in the design of energy saving policies,given that China has entered a“New Normal”of economic development.In fact,enhancing electricity productivi...Electricity productivity is regarded as a major assessment indicator in the design of energy saving policies,given that China has entered a“New Normal”of economic development.In fact,enhancing electricity productivity in an all-round way,as is one of the binding indicators for energy and environmental issues,means that non-growth target of total electric energy consumption in the economic development is feasible.The Gini coefficient,Theil index,and Mean log deviation are utilized to measure regional differences in China’s electricity productivity from 1997 to 2016 in five regions,and conditionalβconvergence is empirically analyzed with the spatial Durbin model.The results show that:(1)China’s electricity productivity is improving,while the overall feature is that the eastern area has a higher efficiency than the western area.(2)The difference in electricity productivity is the smallest in the northeast and the largest in the northwest.Interregional difference plays an important role and is the main cause for the differences.(3)The electricity productivity in China exhibitsβconvergence,except for the northwest.The positive driving factor is urbanization level(0.0485%),and the negative driving factor is FDI(–0.0104%).Moreover,the urbanization rate(0.0669%),foreign direct investment(0.0960%),and the industrial structure(–0.0769%)have a spatial spillover effect on improving regional electricity productivity.Based on this conclusion,the study provides some recommendations for saving energy policy design in China’s power industry.展开更多
Taking 14 prefecture-level cities in Guangxi as an object,this paper explored the difference of cultivated land utilization efficiency in Guangxi,comprehensively evaluated the economic,social,and ecological aspects,an...Taking 14 prefecture-level cities in Guangxi as an object,this paper explored the difference of cultivated land utilization efficiency in Guangxi,comprehensively evaluated the economic,social,and ecological aspects,and analyzed the regional differences in cultivated land use efficiency in Guangxi from 2005 to 2018 based on the improved TOPSIS method.By studying the quantitative change trends and spatial differences of the utilization benefit of cultivated land resources in Guangxi,it came up with recommendations for optimizing the allocation of cultivated land from the quantity and quality of cultivated land.It is intended to provide a scientific and theoretical reference for improving the use efficiency of cultivated land in Guangxi.展开更多
The urban agglomeration in the middle reaches of the Yangtze River(UAMRYR)is a key area to promote the central region rise and the green development of the Yangtze River Economic Belt.In this paper,an evaluation index...The urban agglomeration in the middle reaches of the Yangtze River(UAMRYR)is a key area to promote the central region rise and the green development of the Yangtze River Economic Belt.In this paper,an evaluation index system was comprehensively constructed for the green development level of the UAMRYR from five aspects:resource utilization,green environment,green economy,green life,and support mechanisms.Entropy weight-TOPSIS method and multivariate statistical method,including spatial autocorrelation analysis and geographic detectors,were used to analyze the regional differences and influencing factors of the green development level of the UAMRYR from 2008 to 2018.The results showed that:(1)the overall green development level of the UAMRYR showed a fluctuating upward trend from 2008 to 2018,among which the provincial capital cities such as Wuhan,Changsha,and Nanchang,as well as the cities covered by the Poyang Lake urban agglomeration had relatively higher green development levels.(2)The green development level of the 31 cities in the UAMRYR showed insignificant spatial heterogeneity within the study period.Compared with other areas,the green development levels varied greatly among the regions of the Wuhan metropolitan area,which was a typical high-low aggregation type.(3)Green economy,green life,and support mechanisms were the highly influential aspects of the green development of the UAMRYR,and the main influencing factors were the total value added of secondary and tertiary industries,urbanization rate,and fixed asset investment.The explanatory power of the interaction of influencing factors on the green development of the UAMRYR was greater than that of a single factor.This study is intended to provide a reference for the green transformation development and the coordinated development of the“resources-environment-economy”in the UAMRYR.展开更多
The Paris Agreement aims to limit global warming to well below 2.00℃and pursue efforts to limit the temperature increase to 1.50℃.However,the response of climate change to unbalanced global warming is affected by sp...The Paris Agreement aims to limit global warming to well below 2.00℃and pursue efforts to limit the temperature increase to 1.50℃.However,the response of climate change to unbalanced global warming is affected by spatial and temporal sensitivities.To better understand the regional warming response to global warming at 1.50℃and 2.00℃,we detected the 1.50℃and 2.00℃warming threshold-crossing time(WTT)above pre-industrial levels globally using the Coupled Model Intercomparison Project phase 6(CMIP6)models.Our findings indicate that the 1.50℃or 2.00℃WTT differs substantially worldwide.The warming rate of land would be approximately 1.35–1.46 times that of the ocean between 60°N–60°S in 2015–2100.Consequently,the land would experience a 1.50℃(2.00℃)warming at least 10–20 yr earlier than the time when the global mean near-surface air temperature reaches 1.50℃(2.00℃)WTT.Meanwhile,the Southern Ocean between 0°and 60°S considerably slows down the global 1.50℃and 2.00℃WTT.In 2040–2060,over 98.70%(77.50%),99.70%(89.30%),99.80%(93.40%),and 100.00%(98.00%)of the land will have warmed by over 1.50℃(2.00℃)under SSP(Shared Socioeconomic Pathway)1–2.6,SSP2-4.5,SSP3-7.0,and SSP5-8.5,respectively.We conclude that regional 1.50℃(2.00℃)WTT should be fully considered,especially in vulnerable high-latitude and high-altitude regions.展开更多
The coordinated development between touristization and urbanization is the key to optimizing regional industrial structure and building a long-term dynamic mechanism for urbanization. Based on constructing the measure...The coordinated development between touristization and urbanization is the key to optimizing regional industrial structure and building a long-term dynamic mechanism for urbanization. Based on constructing the measurement index system of touristization and urbanization level, the evaluation model on the coupled and coordinated degree is used in this paper to measure the inter-provincial pattern of the coupled and coordinated relationship between touristization and urbanization in 31 provinces and autonomous regions in China. The results show that the coupled and coordinated relationship between touristization and urbanization is significantly different in different regions, which presents a gradient decline pattern of the highest in the east, the lower in the middle and the lowest in the west. In the future, measures should be taken to promote the coordinated development between touristization and urbanization in accordance with the regional differences and actual development needs.展开更多
China's rapid economic development leads to a series of environmental problems in the long run,such as air pollution.Environmental pollution has become a bottleneck restricting the sustainable development of China...China's rapid economic development leads to a series of environmental problems in the long run,such as air pollution.Environmental pollution has become a bottleneck restricting the sustainable development of China's economy.As such,pollution has become a key issue for China as让tries to continuously improve environmental quality and establish a harmonious coexistence between man and nature.This paper uses spatial econometric analysis to empirically test the existence of the Environmental Kuznets Curve(EKC)in China while also examining the impact of financial development on its inflection point by applying Air Quality Index and PM_(2.5) data of 283 prefecture-level cities in China from 2015 to 2017.Findings from this study indicate that the EKC of air pollution in the whole country presents an inverted U-shape based on both the traditional and new EKC models.After testing the sub-sample in different areas,the EKC still presents an inverted U-shape based on the new EKC model in the eastern and central areas,though not in the western area.In considering the moderating role of financial development based on the new EKC model,we find that the increase of financial depth will cause the EKC inflection point to shift to the left on the national scale and in the eastern region,while the effect of the financial breadth will be largely insignificant.With regard to the central area,both the breadth and the depth of financial development will significantly shift the inflection point to the right,delaying the arrival of the EKC inflection point.Therefore,the local authority of each area should formulate differentiated financial development policies to promote the early arrival of the EKC inflection point.展开更多
https://www.sciencedirect.com/journal/building-and-environment/vol/172/suppl/C Volume 172,April 2020(1)City-scale single family residential building energy consumption prediction using genetic algorithm-based Numerica...https://www.sciencedirect.com/journal/building-and-environment/vol/172/suppl/C Volume 172,April 2020(1)City-scale single family residential building energy consumption prediction using genetic algorithm-based Numerical Moment Matching technique,by Elham Jahani,Kristen Cetin,In Ho Cho,Article 106667Abstract:Grow ing energy consumption in urban areas has increased the importance of planning for future energy systems.展开更多
Environmental regulation and industrial upgrading are the key to achieve win-win results for both economy and the environment. After environmental regulation tools are divided into market incentive and command control...Environmental regulation and industrial upgrading are the key to achieve win-win results for both economy and the environment. After environmental regulation tools are divided into market incentive and command control types,based on the provincial-level data of 30 provinces( cities and regions) in China from 2004 to 2016,the impact of environmental regulation on industrial upgrading and its transmission paths are empirically tested through an intermediary effect model. Technological innovation,FDI and capital market development all meet intermediary conditions,and the market incentive type is more dependent on technological innovation,while the command control type is more dependent on FDI and capital market development.The impact of the two environmental regulation tools on industrial upgrading is further studied. The results show that there is an " inverted U-shaped" relationship between the command control type and industrial upgrading,while there is a " U-shaped" relationship between the market incentive type and industrial upgrading,and there are also certain regional differences in the impact of environmental regulation on industrial upgrading.展开更多
This study constructs a theoretical framework to analyze the impact of local governmentled construction land supply(LGCLS)strategies on urban innovation.It uses data related to 265 cities in China from 2005 to 2019 fo...This study constructs a theoretical framework to analyze the impact of local governmentled construction land supply(LGCLS)strategies on urban innovation.It uses data related to 265 cities in China from 2005 to 2019 for empirical analysis.Its conclusions are as follows.For development stage differences,the impact of LGCLS strategies on urban innovation exhibited an inverted U shape with economic growth.The inflection point occurred when the per capita GDP equaled approximately RMB23,101 in 2008.For regional diferences,the inflection point in eastern China is higher and earlier than that in central and western China;before the inflection point,the positive infuence was more obvious in the central and western regions,whereas after the inflection point,the negative influence was more obvious in the eastern region.For the eastern Yangtze River Delta urban agglomerations and the northwestern resource-based urban agglomerations with relatively high per capita GDP,the negative impact of LGCLS strategies on urban innovation occurred earlier and showed spatial agglomeration characteristics.展开更多
基金supported by the National Natural Science Foundation of China(Grant Nos.42271421 and 41930102)。
文摘Material exchange frequently occurs in gullies,and thus the relationship between a gullynetwork structure and sediment transport potential has attracted considerable interest.However,previous researches ignored the difficulty of material transport from sources to sinks,and did not quantify the connectivity of a network structure.In this study,we used a graph model structure to model gully networks of six typical sample areas in the Loess Plateau of China and quantified gully network connectivity using four indexes:average node strength,accessibility from sources to sinks,potential flow,and network structural connectivity index.Results show that:(1)Reflected by different quantitative indexes,the trends of gully network connectivity in different regions are similar.From north to south,the connectivity of a sample area first increases and then decreases.(2)The more mature gullies have stronger network connectivity.Small resistance is conducive to material transport in the gullies.(3)The node connectivity index of the gully network shows a significant aggregation distribution in space,and node connectivity on the main channel is often stronger than that on the branch trench.These results not only deepen the understanding of the process and mechanism of loess gully geomorphic development and evolution but also provide a reference for geomorphic studies.
基金supported by the National Natural Science Foun‐dation of China[Grant No.72004124,72373084]Shandong Provin‐cial Education Department,China[Grant No.2022RW-064]+1 种基金Depart‐ment of Science and Technology of Shandong Province,China[Grant No.2022RKY04002]Humanities and Social Sciences Project of Shan‐dong Province,China[Grant No.2022-YYJJ-32].
文摘Urban green innovation(UGI)is essential to environmental protection,ecological conservation,and high quality economic growth.Using green patents,our study assessed the level of UGI of 287 Chinese cities at and above the prefecture level.Then,using the Dagum Gini coefficient,kernel density estimation(KDE),and con‐vergence models,we examined regional differences,distribution dynamics,and convergence of UGI across China.The study’s findings are as follows:(1)Overall,regional differences in UGI tended to narrow,and the main contributor to these differences was the difference between economic zones.(2)KDE showed that the level of UGI was rising,which was polarized within each economic zone.(3)The national UGI in economic zones other than the Northeast and Middle Yellow River Economic Zones featured significantσconvergence,while each economic zone showed absolute and conditionalβconvergence.
基金supported by National Natural Science Foundation of China[Grant number.71673034]Postdoctoral Research Founda‐tion of China[Grant number.2021M692654]+1 种基金Natural Science Basic Research Program of Shaanxi Province[Grant number.2020JQ282]Social Science Foundation of Shaanxi Province[Grant number.2020R042].
文摘To achieve the goals of carbon peaking and carbon neutrality and maintain high-quality economic growth,China is currently striving to improve the quality of development of its power sector.In this regard,revealing the regional differences and evolutionary trends in the development quality of China’power sector has a high value to inspire the next improvement direction toward how to integrate regional power recourses to an overall optimization level.Motived by this purpose,this paper uses the entropy method to evaluate the com‐prehensive and subsystem indices of the development quality of the power industry,and reveals their re‐gional differences and evolutionary trends with the help of the Dagum Gini coefficient and Kernel density es‐timation methods.The findings show that:There are obvious regional differences in the development quality of China’s power industry,and the differences are steadily declining in all regions except the West.Regional differences are mainly derived from inter-regional differences,with the largest inter-regional differences in the East-Northeast region.Intra-regional differences show a distribution pattern of East>West>North‐east>Center.
基金supported by the State Grid Science and Technology Project (1300-202157362A-0-0-00).
文摘As an essential infrastructure,the rural power grid is vital in promoting agricultural and rural carbon sequestration and improving rural energy electrification.It is necessary to carry out in-depth research on its comprehensive efficiency.Based on the requirements of“double carbon”and rural revitalization strategy for the rural Power Grid,this paper focuses on the modernization and low-carbon transformation of the rural Power Grid.It constructs an input-output index system for the investment efficiency of the rural Power Grid in China under the new situation.It uses the primary data of the rural Power Grid of 30 prefecture-level cities in China from 2019 to 2021 to evaluate the investment efficiency of the rural Power Grid in China through a three-stage DEA model.The empirical results show that:considering the regional differences,the comprehensive efficiency of the rural Power Grid in backward areas is significantly improved;that is,the three-stage DEA method can more objectively evaluate the comprehensive efficiency of the rural Power Grid.In the context of the continued promotion of the rural revitalization strategy,to improve the comprehensive efficiency of the rural Power Grid,it is necessary to improve the technical level of the rural Power Grid further and appropriately expand the scale of investment in the rural Power Grid.
文摘Purpose: Obtaining high peak bone mass (PBM) and maintaining bone mass is important for the prevention of osteoporosis. This study aimed to examine the regional differences in bone mineral density and factors associated with its acquisition from exercise. Design: The study population included 75 women of 18 - 22 years of age in East Japan and 104 women of 18 - 27 years of age in West Japan. The speed of sound (SOS) of the calcaneus was measured, and the young adult mean (%YAM) was calculated from the SOS. The subjects’ medical history, family history of osteoporosis, and exercise habits were examined using a self-administered questionnaire. Results: There were a significantly greater number of subjects with low %YAM in West Japan. The exercise history and exercise time were significantly higher in West Japan, and the exercise intensity score tended to be higher in East Japan during junior high and high school. A multiple regression analysis by region revealed that the following factors had a significant positive association with the SOS: exercise intensity at elementary school and outdoor sports at junior high school in East Japan;and exercise time at elementary school, muscle mass, and outdoor sports at junior high school in West Japan. On the other hand, exercise time in junior high school in West Japan showed a negative association with the SOS. Conclusions: Regional differences in bone mineral density existed, suggesting a trend toward lower bone mineral density in West Japan. Exercise history and time tended to be higher in West Japan, and exercise intensity scores tended to be higher in East Japan, suggesting that exercise intensity may be more important than exercise time for obtaining bone mineral density.
基金the Strategic Priority Research Program of the Chinese Academy of Sciences(XDA19070501)the National Natural Science Foundation of China(41730751&41671066)the International Partnership Program of Chinese Academy of Sciences(131C 11KYSB20160061,Y560L01001).
文摘Global warming triggers shrinking and thinning of glaciers worldwide,with potentially severe implications for human society.However,regional differences in glacier retreat and its relationship with climatic characteristics have not been conclusively demonstrated.In this study,regional changes in global glaciers based on two primary features,area change and mass balance,were investigated on the basis of data collected from published research on glacier changes.Results show that during the period 1980—2015,the rate of global glacier area shrinkage was 0.18%per year and that of global glacier mass loss was 0.25 m w.e.per year.Retreat of glaciers located at low and middle latitudes was characterized by severe area shrinkage and mass loss.Correspondingly,in the Arctic,deglaciation was characterized by ice thinning due to a low area reduction but relatively high mass loss rate.However,glaciers in high southern latitudes were in a relatively stable status.High Mountain Asia exhibited the lowest rate of area shrinkage and mass loss among glaciers located at low and middle latitudes,and a slower rate of mass loss compared with the global average.Glaciers in the Tropical Andes exhibited the fastest rate of glacier area shrinkage(—1.6%per year),whereas Antarctic and Subantarctic glaciers showed the lowest rate(—0.11%per year).For mass balance,the most negative occurred at Southern Andes(—0.81 m w.e.per year),followed by Alaska(-0.74 m w.e.per year).Only the Antarctic and Subantarctic experienced small mass gain(0.04 m w.e.per year).High levels of correlation are found between the rates of glacier retreat and annual average temperature and annual total precipitation instead of their trends.The variability of the surface climate conditions in the glacier environment plays a key role in driving these regional differences in global glacier retreat.
文摘Based on data over 31 provinces and cities in China from2006 to 2013,this thesis first divides those 31 provinces and cities into four economic regions including northeastern region,central region,eastern region and western region.Based on data over 31 provinces and cities in China from 2006 to 2013,those 31 provinces and cities were devided into four economic regions in this thesis,including northeastern region,central region,eastern region and western region.Then,it takes international tourism foreign exchange earnings as the dependent variable,the four economic regions as the factor to measure the difference of international tourism foreign exchange earnings in different regions,and finds out the main reasons of it.Through the one-way variance analysis on international tourism foreign exchange earnings,we can know that international tourism foreign exchange earnings have differences in different regions apparently.Besides,significant differences can be found between northeastern and central regions as well as eastern and western regions,while it is not the same case between the central and western regions.
文摘The improvement of the technical efficiency of energy use has been widely seen as an important way to alleviate energy scarcity.However,the energy rebound effect demonstrates the vulnerability and unsustainability of alleviating energy scarcity relying on technology.Under the background of the consistent development of energy factor market,it is of great importance to explore the paths and differences of energy source allocation constrained by technology and cost to promote the sustainable use of energy.This study analyzed the regional differences and threshold characteristics in the impact of the technical and cost efficiency of energy use on energy scarcity using the instrumental variable-two-stage least square method,based on the panel data of Chinese provinces from 2003 to 2017.The results showed that:①Technology and price were the critical forces of the technical and cost efficiency of energy use.They changed the degree of use of surplus production factors by affecting the complementary and replacement demand relationship between energy and non-energy factors.Meanwhile,the impact of energy use efficiency on energy scarcity showed regional and time features due to the different technology capabilities and different levels of market development in different regions and different time.②The alleviation of energy scarcity at the national level relied on the improvement of energy cost efficiency.At the regional level,the alleviation of energy scarcity in central China came from the improvement of the technical efficiency of energy use.However,the alleviation of energy scarcity in the eastern and western regions was due to the improvement of energy cost efficiency.③Constrained by the economic development,openness,science and technology input and the industrial development structure,the impact of the technical and cost efficiency of energy use on energy scarcity demonstrated a nonlinear feature.And structural mutation occurred after passing a specific‘inflection point’,which showed a significant threshold feature.Therefore,energy price should play an important role in energy use and it is necessary to pay attention to the regional differences and time characteristics of energy economic development to promote the sustainable development of energy resources.
文摘City size distribution is of interest because of a number of key stylized facts, including notably Zipf's law for cities and the importance of urban primacy. But a new and more efficient method Gini index can be used for calculating regional city size distribution. This paper begins by developing a calculation method for the Gini index, dividing the whole country into 26 areas and then calculating each area's Gini index value. Based on these calculation results, this paper gives a preliminary study on regional differences of its city size distribution and the dynamics.
基金supported by Funds for the National Natural Science Foundation of China Youth Project(Grant Nos.71103120&51507099)Shanghai Social Science Planning General Project(Grant No.2018BGl019).
文摘Electricity productivity is regarded as a major assessment indicator in the design of energy saving policies,given that China has entered a“New Normal”of economic development.In fact,enhancing electricity productivity in an all-round way,as is one of the binding indicators for energy and environmental issues,means that non-growth target of total electric energy consumption in the economic development is feasible.The Gini coefficient,Theil index,and Mean log deviation are utilized to measure regional differences in China’s electricity productivity from 1997 to 2016 in five regions,and conditionalβconvergence is empirically analyzed with the spatial Durbin model.The results show that:(1)China’s electricity productivity is improving,while the overall feature is that the eastern area has a higher efficiency than the western area.(2)The difference in electricity productivity is the smallest in the northeast and the largest in the northwest.Interregional difference plays an important role and is the main cause for the differences.(3)The electricity productivity in China exhibitsβconvergence,except for the northwest.The positive driving factor is urbanization level(0.0485%),and the negative driving factor is FDI(–0.0104%).Moreover,the urbanization rate(0.0669%),foreign direct investment(0.0960%),and the industrial structure(–0.0769%)have a spatial spillover effect on improving regional electricity productivity.Based on this conclusion,the study provides some recommendations for saving energy policy design in China’s power industry.
基金Youth Program of Humanities and Social Science Project of the Ministry of Education(17YJC79004)Program of National Natural Science Foundation of China(71803104)Qingchuang Science and Technology Support Plan for Colleges and Universities in Shandong Province(2019RWE009).
文摘Taking 14 prefecture-level cities in Guangxi as an object,this paper explored the difference of cultivated land utilization efficiency in Guangxi,comprehensively evaluated the economic,social,and ecological aspects,and analyzed the regional differences in cultivated land use efficiency in Guangxi from 2005 to 2018 based on the improved TOPSIS method.By studying the quantitative change trends and spatial differences of the utilization benefit of cultivated land resources in Guangxi,it came up with recommendations for optimizing the allocation of cultivated land from the quantity and quality of cultivated land.It is intended to provide a scientific and theoretical reference for improving the use efficiency of cultivated land in Guangxi.
基金supported by the Strategic Priority Research Program of the Chinese Academy of Sciences(Grant No.XDA23040304)the National Natural Science Foundation of China(Grant Nos.41890822&42101043)。
文摘The urban agglomeration in the middle reaches of the Yangtze River(UAMRYR)is a key area to promote the central region rise and the green development of the Yangtze River Economic Belt.In this paper,an evaluation index system was comprehensively constructed for the green development level of the UAMRYR from five aspects:resource utilization,green environment,green economy,green life,and support mechanisms.Entropy weight-TOPSIS method and multivariate statistical method,including spatial autocorrelation analysis and geographic detectors,were used to analyze the regional differences and influencing factors of the green development level of the UAMRYR from 2008 to 2018.The results showed that:(1)the overall green development level of the UAMRYR showed a fluctuating upward trend from 2008 to 2018,among which the provincial capital cities such as Wuhan,Changsha,and Nanchang,as well as the cities covered by the Poyang Lake urban agglomeration had relatively higher green development levels.(2)The green development level of the 31 cities in the UAMRYR showed insignificant spatial heterogeneity within the study period.Compared with other areas,the green development levels varied greatly among the regions of the Wuhan metropolitan area,which was a typical high-low aggregation type.(3)Green economy,green life,and support mechanisms were the highly influential aspects of the green development of the UAMRYR,and the main influencing factors were the total value added of secondary and tertiary industries,urbanization rate,and fixed asset investment.The explanatory power of the interaction of influencing factors on the green development of the UAMRYR was greater than that of a single factor.This study is intended to provide a reference for the green transformation development and the coordinated development of the“resources-environment-economy”in the UAMRYR.
基金Under the auspices of the Second Tibetan Plateau Scientific Expedition and Research Program(STEP)(No.2019QZKK020104)the National Natural Science Foundation of China(No.41571062,42101122)+2 种基金the Fundamental Research Funds for the Central Universities(No.2020TS100)the Natural Science Foundation of Shaanxi Province,China(No.2023-JC-YB-259)the China Postdoctoral Science Foundation(No.2017M610622)。
文摘The Paris Agreement aims to limit global warming to well below 2.00℃and pursue efforts to limit the temperature increase to 1.50℃.However,the response of climate change to unbalanced global warming is affected by spatial and temporal sensitivities.To better understand the regional warming response to global warming at 1.50℃and 2.00℃,we detected the 1.50℃and 2.00℃warming threshold-crossing time(WTT)above pre-industrial levels globally using the Coupled Model Intercomparison Project phase 6(CMIP6)models.Our findings indicate that the 1.50℃or 2.00℃WTT differs substantially worldwide.The warming rate of land would be approximately 1.35–1.46 times that of the ocean between 60°N–60°S in 2015–2100.Consequently,the land would experience a 1.50℃(2.00℃)warming at least 10–20 yr earlier than the time when the global mean near-surface air temperature reaches 1.50℃(2.00℃)WTT.Meanwhile,the Southern Ocean between 0°and 60°S considerably slows down the global 1.50℃and 2.00℃WTT.In 2040–2060,over 98.70%(77.50%),99.70%(89.30%),99.80%(93.40%),and 100.00%(98.00%)of the land will have warmed by over 1.50℃(2.00℃)under SSP(Shared Socioeconomic Pathway)1–2.6,SSP2-4.5,SSP3-7.0,and SSP5-8.5,respectively.We conclude that regional 1.50℃(2.00℃)WTT should be fully considered,especially in vulnerable high-latitude and high-altitude regions.
基金supported by the National Natural Science Foundation of China(Grant No.41471131)the Training Program for 100 Young Academic Leaders of Nankai University
文摘The coordinated development between touristization and urbanization is the key to optimizing regional industrial structure and building a long-term dynamic mechanism for urbanization. Based on constructing the measurement index system of touristization and urbanization level, the evaluation model on the coupled and coordinated degree is used in this paper to measure the inter-provincial pattern of the coupled and coordinated relationship between touristization and urbanization in 31 provinces and autonomous regions in China. The results show that the coupled and coordinated relationship between touristization and urbanization is significantly different in different regions, which presents a gradient decline pattern of the highest in the east, the lower in the middle and the lowest in the west. In the future, measures should be taken to promote the coordinated development between touristization and urbanization in accordance with the regional differences and actual development needs.
基金the financial support of the Humanities and Social Science Foundation of the Chinese Ministry of Education[Grant num-ber.20YJC630104]the National Natural Science Foundation of China[Grant number.71403120,Grant number.72003157]+1 种基金the National Social Science Foundation of China[Grant number.18ZDA052,Grant number.19ZDA074)the Fundamental Research Funds for the Central Universities[Grant number.JBK2002017].
文摘China's rapid economic development leads to a series of environmental problems in the long run,such as air pollution.Environmental pollution has become a bottleneck restricting the sustainable development of China's economy.As such,pollution has become a key issue for China as让tries to continuously improve environmental quality and establish a harmonious coexistence between man and nature.This paper uses spatial econometric analysis to empirically test the existence of the Environmental Kuznets Curve(EKC)in China while also examining the impact of financial development on its inflection point by applying Air Quality Index and PM_(2.5) data of 283 prefecture-level cities in China from 2015 to 2017.Findings from this study indicate that the EKC of air pollution in the whole country presents an inverted U-shape based on both the traditional and new EKC models.After testing the sub-sample in different areas,the EKC still presents an inverted U-shape based on the new EKC model in the eastern and central areas,though not in the western area.In considering the moderating role of financial development based on the new EKC model,we find that the increase of financial depth will cause the EKC inflection point to shift to the left on the national scale and in the eastern region,while the effect of the financial breadth will be largely insignificant.With regard to the central area,both the breadth and the depth of financial development will significantly shift the inflection point to the right,delaying the arrival of the EKC inflection point.Therefore,the local authority of each area should formulate differentiated financial development policies to promote the early arrival of the EKC inflection point.
文摘https://www.sciencedirect.com/journal/building-and-environment/vol/172/suppl/C Volume 172,April 2020(1)City-scale single family residential building energy consumption prediction using genetic algorithm-based Numerical Moment Matching technique,by Elham Jahani,Kristen Cetin,In Ho Cho,Article 106667Abstract:Grow ing energy consumption in urban areas has increased the importance of planning for future energy systems.
文摘Environmental regulation and industrial upgrading are the key to achieve win-win results for both economy and the environment. After environmental regulation tools are divided into market incentive and command control types,based on the provincial-level data of 30 provinces( cities and regions) in China from 2004 to 2016,the impact of environmental regulation on industrial upgrading and its transmission paths are empirically tested through an intermediary effect model. Technological innovation,FDI and capital market development all meet intermediary conditions,and the market incentive type is more dependent on technological innovation,while the command control type is more dependent on FDI and capital market development.The impact of the two environmental regulation tools on industrial upgrading is further studied. The results show that there is an " inverted U-shaped" relationship between the command control type and industrial upgrading,while there is a " U-shaped" relationship between the market incentive type and industrial upgrading,and there are also certain regional differences in the impact of environmental regulation on industrial upgrading.
基金the Humanities and Social Sciences Foundation of Ministry of Education of China(No.22YJC630132)the Natural Science Foundation of Jiangsu Province(No.BK20221026)+1 种基金the National Natural Science Foundation of China(No.42101272)the Natural Science Foundation of Shandong Province(No.ZR2021QD085)。
文摘This study constructs a theoretical framework to analyze the impact of local governmentled construction land supply(LGCLS)strategies on urban innovation.It uses data related to 265 cities in China from 2005 to 2019 for empirical analysis.Its conclusions are as follows.For development stage differences,the impact of LGCLS strategies on urban innovation exhibited an inverted U shape with economic growth.The inflection point occurred when the per capita GDP equaled approximately RMB23,101 in 2008.For regional diferences,the inflection point in eastern China is higher and earlier than that in central and western China;before the inflection point,the positive infuence was more obvious in the central and western regions,whereas after the inflection point,the negative influence was more obvious in the eastern region.For the eastern Yangtze River Delta urban agglomerations and the northwestern resource-based urban agglomerations with relatively high per capita GDP,the negative impact of LGCLS strategies on urban innovation occurred earlier and showed spatial agglomeration characteristics.
